# GUI Frontend Roadmap: Lumacs with GTK4 (gtkmm)

This document outlines the phased approach to integrate a graphical frontend into Lumacs, utilizing GTK4 with its C++ bindings (gtkmm). The goal is to provide a rich, native user experience while leveraging the existing C++ core and Lua extensibility.

## Phase 0: Preparation (Current State)

*   **Status**: Complete
*   **Description**: Core editor logic (EditorCore, Buffer) is decoupled from the UI. An abstract `Face` system is implemented, allowing for UI-agnostic styling definitions.
*   **Key Achievements**:
    *   Abstract `Face` system in `include/lumacs/face.hpp`
    *   `Theme` system refactored to manage `Face` definitions
    *   `Buffer` stores `face_name` for styling ranges
    *   `NcursesEditor` renders Faces to best of its ability (colors, bold, italic)

## Phase 1: Abstract UI Interface Extraction

*   **Status**: Complete
*   **Goal**: Define a clean separation between `EditorCore` and any UI frontend.
*   **Achievements**:
    *   `IEditorView` interface defined in `include/lumacs/ui_interface.hpp`.
    *   `NcursesEditor` refactored to `TuiEditor` implementing `IEditorView`.
    *   `EditorCore` decoupled from specific UI implementation.

## Phase 2: GTK4 Environment Setup & Basic Window

*   **Status**: Complete
*   **Goal**: Integrate GTK4 into the build system and display a minimal window.
*   **Achievements**:
    *   Updated `CMakeLists.txt` with `gtkmm-4.0` dependency.
    *   Created `src/gtk_editor.cpp` implementing `IEditorView`.
    *   Single binary architecture with `-nw` fallback.

## Phase 3: Displaying Buffer Content

*   **Status**: Complete
*   **Goal**: Render the active buffer's text content within the GTK window.
*   **Achievements**:
    *   Implemented `GtkEditor::on_draw` using Cairo and Pango.
    *   Text rendering works with font metrics.

## Phase 4: Styling with Faces

*   **Status**: Complete
*   **Goal**: Implement the `Face` system within `GtkEditor` to render styled text.
*   **Achievements**:
    *   Mapped `FaceAttributes` (foreground color) to Cairo source.
    *   Cursor rendering implemented.

## Phase 5: Input Handling & Minibuffer

*   **Status**: Complete (Prototype)
*   **Goal**: Capture keyboard input and integrate with the minibuffer and other interactive UI elements.
*   **Achievements**:
    *   Implemented `GtkEditor::on_key_pressed`.
    *   Mapped GDK key events to Lumacs key strings (with modifiers).
    *   Minibuffer command input works.

## Phase 6: Full UI Feature Parity

*   **Status**: In Progress
*   **Goal**: Implement all existing features of `TuiEditor` (window splits, status lines, messages, marks, regions) in `GtkEditor`.
*   **Completed Tasks**:
    1.  ~~**Stability**~~: Fix crash on exit. ✅ (2025-11-27)
        - Fixed double-free by clearing event callbacks before view destruction
        - Added null safety checks in draw and event handlers
        - Proper GTK Application/Window lifetime management
    2.  ~~**Character Input**~~: Self-insert for printable characters. ✅ (2025-11-27)
        - Added fallback handler for unbound printable keys
        - Characters now render correctly when typed
    3.  ~~**Cursor Rendering**~~: Visible inverted block cursor. ✅ (2025-11-27)
        - Cursor draws with theme color and inverted character
*   **Remaining Tasks**:
    1.  **Status Line/Modelines**: Render status bars for each window. (Basic implementation done)
    2.  **Window Splits**: Implement window splitting logic using GTK containers (e.g., `Gtk::Paned` or `Gtk::Grid`).
    3.  **Scrolling**: Implement visual scrolling (viewport offset).

## Future Considerations

*   **High-DPI Support**: Ensure crisp rendering on high-resolution displays.
*   **Accessibility**: Integrate with GTK's accessibility features.
*   **Native File Dialogs**: Use `Gtk::FileChooserDialog` for `find-file` and `save-as`.